1. Antenna Matching Techniques
Chapter 4
Antenna Matching Techniques
Part 1

2. Table of Contents Transmission line principles
Lumped matching circuits
Reactive matching circuits
Power splitting/combining networks
Impedance matching and Smith Chart
1 week

3. 4.1 Transmission line and principles

4. Matching Network
minimum power loss in the feed line & maximum power delivery
linearizing the frequency response of the circuit
improving the S/N ratio of the system for sensitive receiver components (lownoise amplifier, etc.)
reducing amplitude & phase errors in a power distribution network (such as antenna array-feed network)

5. Matching Network Factors in the selection of matching networks
complexity - bandwidth requirement (such as broadband design)
adjustability - implementation (transmission line, chip R/L/C elements ..)

6. S11, Reflection Coefficient, and Return Loss
Should yield +ve value a
(S11)
High RL, less reflection b
*Antenna is one port

7. 4.2 Lumped Matching Networks
L – Type Matching Network

8. Notes:
Determining L – Type Matching Network

9. Determining L – Type Matching Network
Notes:
Determining L – Type Matching Network
Normalized admittance changed by,
Normalized impedance changed by,

10. L – Type Matching Network

11. L – Type Matching Network

12. L – Type Matching Network

13. L – Type Matching Network

14. L – Type Matching Network

15. L – Type Matching Network

16. Microstipline matching techniques
From discrete component to microstrip line
Single stub
Double stub

17. Microstipline matching techniques
Quarter Wavelength Matching Network
Only used for pure-resistance matching
Similar like what we did in Lab 3
Will calculate Rin or ZL first, then Z1